MicroRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally modulate gene expression and orchestrate a wide range of biological and pathological processes. The use of high-throughput screening technologies, in particular microscopy-based screenings (also known as high-content screenings), coupled with genome-wide libraries for modulation of miRNA levels, allow for comprehensive functional analysis of each member of the miRNome in different phenotypic cell-based assays. The wealth of information obtained from such screenings spans across various fields of research, including cancer, cardiovascular, cell reprogramming, and infection biology. Here, we provide an overview of the rationale for performing screenings using synthetic libraries of miRNA mimics and inhibitors, and of the microscopy-based miRNA screenings performed to date. Moreover, a list of resources available for such endeavor is provided. Finally, we describe a detailed procedure for a case study where microscopy-based screening using a library of miRNA mimics was performed to identify miRNAs that control infection of epithelial cells by the bacterial pathogen Salmonella. The methodologies described here can be easily adapted for screenings addressing other biological questions.

中文翻译：

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通过基于显微镜的筛选揭示 microRNA 功能

MicroRNA (miRNA) 是小的非编码 RNA，可在转录后调节基因表达并协调广泛的生物和病理过程。使用高通量筛选技术，特别是基于显微镜的筛选（也称为高内涵筛选），再加上用于调节 miRNA 水平的全基因组文库，可以对不同的 miRNome 的每个成员进行全面的功能分析。基于表型细胞的检测。从此类筛查中获得的大量信息跨越了各个研究领域，包括癌症、心血管、细胞重编程和感染生物学。在这里，我们概述了使用 miRNA 模拟物和抑制剂的合成文库进行筛选的基本原理，以及迄今为止进行的基于显微镜的 miRNA 筛选。此外，还提供了可用于此类努力的资源列表。最后，我们描述了一个案例研究的详细程序，其中使用 miRNA 模拟物库进行基于显微镜的筛选，以识别控制细菌病原体沙门氏菌感染上皮细胞的 miRNA。这里描述的方法可以很容易地适用于解决其他生物学问题的筛选。